The figure shows the gear drive with the number of teeth (Z1=31, Z2=32), modulus (m=6), pressure angle (a=20 degrees), crest height coefficient (ha*=1) unchanged. When the gear deflection coefficient is equally distributed, the sliding rate changes with the variation coefficient of center distance.
It can be seen from the diagram that when other parameters remain unchanged, with the increase of variation coefficient of center distance, the actual engagement line length of the gear reduces, i.e. the sliding rate at the root and top of the engagement gear decreases, and the bending degree of the sliding rate curve decreases, thus reducing the wear degree during engagement of the two gears.